Adding machine.



P. R. MGBBRTY.

ADDING MACHINE.

APPLICATION FILED 19313.27, 1904.

' Patented Nov. 2, 1909.

2 SHEETS-SHEET 1.

P. R. MOBERTY.

ADDING MACHINE.

.1.\.1PL1GAT10N*FILED rBB.z7, 1904.

938,501 Patented Nov. 2, 1909.

2 SHEETS-SHEET 2.

- Y entren errar-s reinante ernten,

FRANK R. MCBERTY, F EVANSTON, ELLKNOIS, ASSIGNR 'E0 BURRUUGH DDIG MACHNECOMPANY, OIF DETROIT, MCHIG-AN, A CORPORATGN OF MGHXGN.

' asesor.

ADDING-MACHINE.

Specication'of Letters Patent.

Patented Nov. 2, i900.

To all whom it may concern:

Be it known that ll, FRANK R. MCBERTY, a citizen oi' the United States,residing at Evanston, in the county of @ook and State of Illinois, haveinvented certain new and usefulimprovements in J@adding-Machines,

- ot' which the following is a description, reference being had to theaccompanying drawings, forming part ot this specication.

My invention relates more particularly to electric operating devices forsuch machines, intended to take the place of the handle by which suchmachines are ordinarily manually operated, and in the drawings l haveillustrated my invention as applied to a familiar type of such machinescommonly known as the Burroughs adding machinethe details of whoseconstruction and mode ot operation are illustrated and described invarious Letters Patent of the United States, such as Nos. 504,963,505,078 and 595,864.

in the accompanying drawings, Figure 1 shows an outline of such addingmachine, in side elevation, with a diagrammatic illustration of oneadaptation of my invention thereto; Figs. 2, 3 and l show details ot theself-locking magnetic switch employed in the circuit shown in Fig. l;and Fig. 5 shows a modified adaptation of the invention to the samemachine.

The same letters ot reference are employed to indicate correspondingparts in the several views. j

ln Fig. l, A represents an addi machine of the t pe lreferred to, whichis operated by a roc shaft B, to which is ordinarily secured anoperating handle for the manual operation of the machine, the completeoperation o the machine consisting in depressing the necessary keys torepresent the amount to be added and printed, and then pulling thehandle of the rock shait'torward to its limit of movement (about aquarter.

turn oit the shaft) andreleasing it, whereupon the handle and shaft andmechanism within the machine will be restored to normal position bysuitable springs located within the machine for that purpose.

In the present instance l secure to the rock shatt- B a. dependinggear-toothed sector C, which meshes with a pinion D fast upon thearmature shaft E of an electric motor F located in a circuit from agenerator G. rl`his circuit is provided with two openings or breaks, onecontrolled by a knife blade switch H, and the other by a push-button l,while interposed in the circuit at J is a selfloclring magnetic switchwhose function and mode of operation will be hereinafter eirplained rlheknife-blade switch H is arranged to be automatically operated by twocontact arm-s a o projecting upward from the sector C, between whicharms the lower endof the switch lol-depends. Under this arrangement ofparts the motor circuit is normally open at the push-button l. When saidbutton is depressed andthe circuit closed at that point, the motorarmature will be rotated in the direction of the arrow, and will swingthe sector C rearward until the arm o contacts with the lower end of theswitch H and swings it forward to openv the .circuit at that point,whereupon the motor will be deprived of current and the restoringsprings within the machine will turn the rock shaft B and sector C andmotor shaft back to normal position, and as they reach such position thelsector arm a will contact with the ltorward'side of the switch H andrestore it to normal position and again close the circuit atthat point.The springs within the machine, or'restoring the parts to normal position, are not shown in the present drawings, but in Fig. 1 l have.illustrated a substitute spring connected to the sect/or C, which willperform the functions of the springs within the machine so far as thereturn of the sector and connected parts to normal positionA isconcerned.

rlhe foregoing description has assumed, for the sake of simpliclty, thatthe circuit has been maintained closed at the push-bu.tton'l bycontinued pressure upon such button, but for the purposeof permittingthe button to be released immediately after the initial closing of the'circuit the self-locking magnetic switch .l and branch circuit adaptedto be closed by it are employed, and this switch is made of such novelconstruction in the present instance as to adapt it for operation byeither a direct or an alternating current, so that either a direct or analter nating current motor may be employed for operating the machine.This switch, whose details are illustrated in Figs. 2, 3 and 4f,comprises a horse-shoe magnet Y), an armature e and axpair of contactsel d secured respectively to the magnet and the armature.

- These contacts are interposed in a branch circuit K, which leads fromone side of the motor circuit to the contact piece cl, and thence by thecontact piece d (when the two contacts are closed together), to theother side of the circuit. The branch K is normally open at the contactsal al', but when the motor circuit is closed at the push-button l andthe magnet thereby energized, the upper end of its armature c will bedrawn toward it andthe branch circuit will be closed at the flow throughthe motor circuit (z'. e., until the circuit is opened at the lmifebladeswitch H in the manner heretofore explained), it follows that thepush-button l may be instantly released, after it has been depressed toinitially close the circuit, and the circuit will thereafter' bemaintained closed through the switch J and branch K.

' rl`his general mode of operation, including the employment of aself-locking magnetic switch J in the circuit, is adapted to eitherdirect or alternating currents, but for use with alternatinfr currents aspecial construe tion of the sel -locking magnetic switch is necessary,one embodiment of which l have illustrated in the drawings and will nowdescribe more in detail.

The armature 0 of the magnet is made comparatively heavy, so as to haveconsiderable inertia, and it is arranged in approximately verticalposition and pivots or swings upon its lower end, which is knife-bladeshape and rests in a suitable seat provided for 1t in the lowerpole-piece of the magnet. This arrangement of the armature inapproximately vert-ical position (inclining slightly forward or awayfrom the polepiece of the magnet at its upper end), permits its inertiato be taken advantage of while still leaving the armature free, to bemoved toward the pole-piece of the magnet with a minimum force. Both thearmature and the magnet core and pole-pieces are constructed of thinlaminas of iron insulated from each other for the prevention of eddycurrents, in order that the magnet may be effectively magnetized byalternating currents of high frequency. Both the magnet and its armatureare surrounded by coils (e and e) located in the motor circuit andreversely wound (Fig. l), so that the upper end of the armature will bevmagnetized with a polarity the reverse of that of the upper o e-pieoeof the ma net and the attractive Orce between them e correspondinglyinesami creased when their coils are energized. llnstead of arrangingthe upper end of the armature to he drawn into direct contact with theupper pole-piece of the magnet, to

vclose the switch, the contacts cl d are employed, and one of them (clin the present instance), is formed of a spring so light that it willreadily yield to pressure when the upper end of the armature is drawntoward the upper pole-piece of the magnet, with the result that afterthe contact points are brought together by the initial movement of thearmature, the latter may be drawn still farther toward the upperpole-piece of the magnet, the spring yielding to permit such furthermovement. Under this construction and arrangements of parts, when the.coils of the magnet and armature are energized by an alternatingcurrent, the upper end of the armature will be drawn toward the upperpole-piece of the magnet, by successive impulses of current, and theswitch be closed and maintained closed at the contacts (Z (Z. Theattraction exerted upon the upper end of the armature by an impulse ofthe current in one direction will draw the armature Atoward the magnet,and the inertia of the armature will be so great that it will not fallaway from the magnet during the intermissions of the current; and theresult will be that the armature will be drawn toward the pole-piece ofthe magnet by successive impulses of the current and the branch circuitbe closed at the switch contacts, and it will be maintained closed atthat point notwithstanding the alternations of the current, for thereason that although the armature of the magnet will be released fromthe attractive force at each reverse impulse or intermission of thecurrent, and will tend to return to normal position and open the branchcircuit, its inertia will prevent its moving far enough toward normalposition to do so during any such reversal of the current, aconsiderable movement of it being accommodated bythe spring contact dwithout actually separating the contacts.

The coils e e are preferably both mounted in fixed position, the coilehaving an opening through it of sufficient. size to permit the play ofthe armature of the magnet without moving the coil itself. The coils eand e are approximately alike, this construction insuring that the coreand the armature shall be magnetized with approximate equality and inco-incident phases. y

As will be understood from the foregoing description, by the employmentof a magnetic switch of the construction described, or of any otherconstruction embodying the essential features described, either a director an alternating current may be used for operating the machine, suchswitch being adapted for use in connection with either a directcurrentniotor, an alternating current motor, or a motor adapted for usewith either current.

Fig. 5 illustrates a modified employment of the self-locking magneticswitch .I adapted to alternating currents, in which one of thepole-pieces of the motor field is itself utilized as the magnet of theswitch. Thus the armature c is pivoted at its lower end to the lowerpole-piece 7) of the field frame of the motor, while its upper endstands in front of and in proximity to the upper polepiece b2 andcarries a yielding spring contact d adapted to coperate with a contact Zsecured to said upper pole-piece. These contacts d d are interposed in abranch line K, connecting the opposite sides of the motor circuit, as inF ig. l. When the circuit is closed at the push-button I and thefield-frame of the motor thereby magnetized, the upper pole-piecethereof Will attract the upper end of the armature c and close thebranch circuit at the switch contactss Z (l, and will maintain thecircuit vclosed through said branch until the circuit is opened at theknife-blade switch H in the manner described. In Fig. 5 this knife-bladeswitch is simply illustrated diagrammatically at the rear of the motor,but it will be understood that the actual arrangement of it will, ormay, be the same as thatsliovvn in F ig. 1.

While I have shown the motor shaft geared directly to the sector carriedby the operating rock shaftvof the machine, I contemplate in'terposing areducing gear between` the motor shaft and sector, so that instead ofcausing the sector and operating shaft to be given their full movementby a single revolution or less of the motor shaft, greater movement ofthe motor shaft may be permitted, so that a smaller and less powerfulmotor may be employed with less eX- penditure of current.

Having thus fully described my inveiition, I claim:

1. In electric operating means for adding machines and the like, thecombination with t-he driving member thereof, andmeans for returningsaid driving member to initial position in each operation of themachine; of a motor circuit, a motor in said circuit for operating saiddriving member, manually operated means for closing the one point, amagnetic switch having its magnet in said circuit, for closing thecircuit and maintaining it closed independently of said manually oerated means, and means operated by the dii'iving member forautomatically opening the circuit; substaiitially as described.

2. In electric operating means for adding machines and the like, thecombination with the driving member thereof, and means for returningsaid driving member to initial position in each operation of themachine;

point, a magnetic switch having its magnet circuit at Iofamotor'circuit, a motor in said circuit for operating said drivingmember, manually operated means forclosing the circuit at one' point, amagnetic switch having its magnet in said circuit, for closing thecircuit aiid maintaining it closed indepeiidently of said manuallyoperated means, means operated by the driving member for automaticallyopening the circuit, and spring-operated means for closing the circuit;substantially as described.

3. Inl electric operating means for adding machines and the like, thecombination with the driving member thereof, and means for returningsaid driving member to initial position in each operation of themachine; ofa motor circuit, a motor in said circuit for operating saiddriving member, manually operated means for closing the circuit at onein said circuit, for closing a branch of the motor circuit in shunt ofthe manually operated means, and means operated by the driving memberfor automatically opening the circuit; substantially as described.

4. In electric operating means for adding machines and the like, thecombination with the driving member thereof, and means for returningsaid driving member to initial position in each operation of themachine; of a motor circuit, a motor in said circuit for operating saiddriving member, manually operated means for closing the circuit at onepoint, a magnetic switch having its magnet in said circuit, for closinga branch of the motor circuit in shunt of the manuallyl operated means,means operated by the driving member for automatically opening thecircuit, and spring-operated means for closing it; substantially asdescribed.

I5. In electric operating .means for adding machines and the like, thecombination with the driving member thereof, and means for returningsaid driving member to initial position in each operation of themachine; of a motor circuit, a motor in said circuit for operating saiddriving member, manually operated means for closing the circuit at onepoint, a magnetic switch having its magnet in said circuit, for closinga branch of the motor circuit in shunt of the manually operated means,means operated by the driving member for automatically opening thecircuit, and spring-operated means for restoring the parts to normalposition and closing the circuit; substantially as described.

6. In electric operating means for adding machines and the like, a motorcircuit, a motor in said circuit for opertaing said machine, manuallyoperated means for closing the circuitat one point, a branch circuitadapted to be closed in'sliiint of said manually operated means, aswitch in said circuit operated by the magnetization of the 1:0

field of the motor, to close said branch circuit, and means operated bythe motor for automatically opening the circuit; substantially asdescribed.

7. In electric operating means for adding machines and the like, a motorcircuit, a motor in said circuit for operating said machine, manuallyoperated means for closing the circuit at one point, a branch circuitadapted to be closed in shunt of said manually operated means, a switchin said cir cuit operated by the magnetization of the field of themotor, to close said branch circuit, means operated by thc motor forautomatically opening the circuit, and springoperated means for closingit; substantially as described.

8. n electric operating means for adding machines and the like, a motorcircuit, a motor in said circuit for operating said machine, manuallyoperated means for closing the circuit at one point, a branch circuitadapted to be closed in shunt of said manually operated means, a switchin said circuit operated by the magnetization of the field of the motor,to close said branch circuit, means operated by the motor forautomatically opening the circuit, and springoperated means forrestoringthe motorshaft and connected parts to normal position and closing thecircuit; substantially as described.

9. In electric operating means for adding machines and the like, thecombination with the driving member thereof, and means for returningsaid driving member to initial pcsition in each operation of themachine; of a motor circuit, a motor in said circuit for operating saiddriving member, a pair of contacts in said circuit adapted to be closedby a push-button or the like, a selflocking magnetic switch interposedin said circuit for closing it in shunt of the push-button and itscontacts, a switch for opening and closing said circuit at anotherpoint, and means operated by the driving member for automaticallyopening said last mentioned switch; substantially as described.

10. In electric operating means for adding machines and the like, thecombination with the driving member thereof, and means for returningsaid driving member to initial position in each operation of themachine; of a motor circuit, a motor in said circuit for operating saiddriving member, a pair of lcontacts in said circuit, adapted to beclosed by a push-button or the like, a self-locking magnetic switchinterposed in said circuit for closing it in shunt of the push-button,and its contacts, a switch for opening and closing said circuit at`another point, means operated by the driving member for automaticallyopening said last-mentioned switch, and spring-operated means forclosing it; substantially as described.

easter 11. 1n electric operating means for adding machines and the like,a motor circuit, a motor in said circuit, a sector fast upon theoperating shaft of the machine and geared to said motor, means formanually closing said circuit, and a switch in said circuit arranged tobe automatically opened by said sector; substantially as described.

12. ln electric operating means for adding machines and the like, amotor circuit, a motor in said circuit, a sector fast upon the operatingshaft of the machine and geared to said motor, a restoring spring forsaid sector, means for manually closing said cir cuit, and a switch insaid circuit arranged to be automatically opened and closed by saidsector; substantially as described.

13. In electric operating means for adding machines and the like, asector C tast upon the operating rock shaft B of the machine, a motorcircuit, a motor F located in said circuit and geared to the sector C, aswitch H in said circuit, and a contact arm a carried by the sector foropening said switch; substantially as described.

14. In electric operating means for adding machines and the like, asector C fast upon the operating rock shaft B of the machine, a motorcircuit, a motor F located in said circuit and geared to the sector C, arestoring spring for said sector, a switch H in said circuit, and a pairof contact arms a a carried by said sector' for opening and closing saidswitch; substantially as described.

15. In combination with a motor magnet, and a source of alternatingcurrent for operating the same, a manually operated switch for closingthe circuit, and a self-locking magnetic switch having its switchcontacts connected in multiple with said manualv switch and its magnetlocated in said circuit, said magnetic switch having an armature of highinertia, and yielding contacts adapted to prolong closure of thecircuit; whereby said magnet is caused to maintain its own circuit whenexcited by alternating currents. 16. In combination with a motor magnetand a source of alternating current for operating the same, a manuallyoperated switch for closing said circuit, and a selflocking magneticswitch having its switch contacts connected in multiple with said manualswitchand its magnet located in said circuit, said magnetic switchhaving an armature of high inertia, the core of said magnet beinglaminated as described, and yielding contacts adapted to prolong closureof the circuit; substantially as described.

17. In a self-locking magnet for excitement by alternating currents,.thecombination with the laminated core, of a heavy armature therefor, andmeans for applying a relatively light retractive force, yieldingcontacts controlled by said armature, adapted to permit fluttering ofthe armature withdescribed.

18. In a self-locking magnetic switch, adapted for excitement byalternating currents, the combination of tWo magnetic members and equalmagnetizing helices therefor,

, the armature member being heavy and being retracted by a relativelyfeeble force, and yielding switch contacts controlled by said armatureto be closed when the armature is attracted; substantially as described.

19. In electric operating means for adding machines and the like, the.ycombination With a reciprocatory driving memberof such machmespring-drawn 1n one directlon, ot 4a motor circuit, afmotor in saidcircuit for operating the said driving member `in oppositionto itsspring, manually operated means for closing the circuit at vone point, amag-4 netic switch having its magnet in said circuit, for closing thecircuit and maintaining it closed independently of said manuallyoperated means, and 'means for automatically opening the circuit bythereciprocatory driving member of the vmachine as itis brought by themotor to the limit of its movement in one direction; substantially asdescribed. l 4

20. In electric operating means for adding machines and the like, thecombination with a reciprocatoryrdriving member of such machinespring-drawn in one direction, of a motor circuit, a motor in saidcircuit for operating the said driving member in oppos1tion to itsspring, manually operated means for closing the clrcuit at one point, amagnetic switch having its magnet in said circuit, for closingthecircuit and maintaining it closed independently of said i manuallyoperated means, means for .automatically opening the circuit by thereciprocatory driving member of the machine as it is brought by themotor to the limit of its movement in one direction, and means forclosing the circuit by said member When returned by its spring to thelimit of its movement. in the opposite direction; substantially asdescribed.

21. In electricoperating means for adding machines and the like, thecombination with a reciprocatory driving member of such machinespring-drawn in one direction, of a motor circuit, a motor in saidcircuit for Operating the said driving member in opposition to itsspring, manually operated means for closing a branch of the motorcircuit in shunt of the manually operated means, and means forautomatically opening the circuit by the reciprocatory driving member ofthe machine as it is brought by the motor to the limit of-itsmovement inone direction.

22. In electric operating means for adding machines and the like, thecombination With a reciprocatory driving member of such machinespring-drawn in one direction, of a motor circuit, va motor in saidcircuit for operating the saidy driving member in opposition to itsspring, manually operated means for closing a branch of the motorcircuit in shunt of the manually operated means, means for automaticallyopening the circuit by the reciprocatory drivingv member of the machineas it is brought by the motor to the limit of its movement in onedirection, and means for closing the circuit by said member whenreturned by its spring to the limit of its movement in the oppositedirection; sul stantially as described.

FRANK R. MCBERTY.

Witnesses:

LoUIs B. ERWIN, EDWARD RECTOR.

